Reversing his own decision from a day before, a judge ruled Thursday that Amy Senser's long-standing refusal to speak with police may not be used against her in her criminal vehicular homicide trial next week.

Hennepin County District Judge Daniel Mabley did not explain why he changed his mind the day after he ruled on 16 motions by the prosecution and defense.

Joseph Daly, a professor at Hamline University School of Law, said he was baffled by Mabley's initial ruling, based on his understanding of the Fifth Amendment. He was heartened by the reversal, which he called rare.

"It is not normal for a judge to reverse himself so publicly and so immediately," Daly said. "I admire a judge willing to do that. These cases are complex, difficult and filled with constitutional dilemmas. Sometimes any human being might make a mistake."

Senser's attorney, Eric Nelson, filed a motion that would bar prosecutors from presenting Senser's silence as evidence. She has refused to speak with investigators, invoking her Fifth Amendment right to avoid self-incrimination, since she came forward as the driver in the hit-and-run crash that killed Anousone Phanthavong, 38, on an Interstate 94 exit ramp in August.

After the switch, Nelson said he appreciated "the court's careful review of the law on this issue."

Senser is charged with three counts of felony criminal vehicular homicide. Prosecutors say she intentionally fled after she hit Phanthavong as he was putting gas in his stalled vehicle at the Riverside Avenue exit. Nelson says Senser didn't know she struck a person when she left the scene that night.

Nelson argued his motion based in part on two Minnesota Supreme Court cases, State vs. Borg and State vs. Dunkel. In the Borg case, prosecutors were allowed to present as evidence the defendant's failure to respond to a letter from a detective because the correspondence was not police questioning. However, the case also made clear that people are protected under the Fifth Amendment from actual questioning, regardless of whether they are under arrest. The second case maintained that it is a due process violation to admit someone's silence as evidence when that person invokes his or her right to an attorney.

Nelson was the first to contact law enforcement on Senser's behalf and repeatedly told authorities that the driver of the vehicle, later identified as Senser, would not give a statement.

Daly likened the judge's rulings on pretrial motions to a referee making calls. In this case, he caught his error on time, Daly said.

"The game hasn't started yet. That's the good thing about it."

Abby Simons  612-673-4921

Abby Simons is the Star Tribune’s Public Safety Editor. Her team covers crime and courts across the metro. She joined the Star Tribune in 2008 and previously reported on crime, courts and politics.